1. Field of the Invention
The invention relates in general to an ink-jet printing module, and more particularly to an ink-jet printing module having a cleaning device and a covering device at two sides of the printing platform.
2. Description of the Related Art
The art of ink-jet technology is relatively well developed. Commercial products such as computer printers, graphics plotters, copiers, and facsimile machines employ ink-jet technology for producing hard copy. The basics of this technology are disclosed, for example, in various articles and patents. One of the main components of the printing machine is a printing module. A conventional printing module is illustrated in FIG. 1A and FIG. 1B.
Referring to FIG. 1A and FIG. 1B, the top view and the side view of the conventional ink-jet printing module are shown, respectively. The ink-jet printing module 100 includes a print-head 102, a guiding bar 104, a printing platform 106, two sides 112a and 112b, a cleaning device 108 and a covering device 110. The side 112a and the side 112b are opposite to each other. The guiding bar 104 is located between the side 112a and the side 112b. One end of the guiding bar 104 is coupled to the side 11 2a and the other end of the guiding bar 104 is coupled to the side 112b. The print head 102 is movable along at the guiding bar 104 so that the print head 102 is able to move backwards and forwards in the direction indicated by the arrow 150. The bottom surface of the print head 102 is a nozzle surface 102a for ink jetting. The printing platform 106 is disposed approximately at the bottom center of the printing module 200.
During or after each printing, ink residue may remain at the nozzle surface 102a. When the ink residue accumulates to a certain amount, it may drop onto the printed document and cause contamination. If the ink residue gets dry on the nozzle surface 102a, nozzle clogging may occur. Therefore, a cleaning device 108 and a covering device 110 are necessary. The cleaning device 108 is typically a wiper to wipe away the ink residue on the nozzle surface 102a. The covering device 110 is typically a cap. The cap 110 is used for providing print head protection and preventing the nozzle from clogging by capping during non-use.
The conventional cleaning device and covering device are formed in a unitary unit, that is, a two-in-one device. The unitary cleaning and covering device is positioned adjacent to one of the two sides of the printing module 100. As a result, the space 160 between the other side 112a and printing platform 106 is left empty. Consequently, the printing module 100 as a whole is unbalanced and its sized is hard to reduce. Furthermore, even only one of the wiper and cap wears out, the whole two-in-one device needs to be replaced.